Smartweeds
The smartweeds belong to the same family as knotweeds and buckwheats. Smartweeds are widely found throughout the freshwater areas of the country, yet only one species is strictly aquatic: water smartweed, P. amphibium. The remainder do quite well in moist soils and along water margins such as pond and ditch banks. They also grow well in cultivated fields during heavy spring and winter rains that soak the ground. In some areas smartweed growth can become so dense that it can completely cover several acres of land.